That whistling noise is actually the what you hear when you're not quite at W.O.T. You'll probably notice that it goes away at W.O.T. and comes back when you're chillin' on the throttle. I KNOW someone has explained this in detail (with pictures) somewhere in here. Do the search.
But that's what it is. And there is no "fixin'" it. And I hate it too! But all I can tell ya is turn the radio up and find that happy medium throttle position where the sound just goes away without you having to be at W.O.T. all the time...


It's the air goin' over the "flap" that let's the air into the T.B. (I know I sounded ignorant there.... )